Collapsible carton



March 6, 1951 L. H. PHILLIPS 2,544,565

COLLAPSIBLE CARTON Filed Oct. 28, 1949 l: I 5L. fnuenfm J2 .6CZLUIEILC'CHPAZIZZZEPS Patented Mar. 6, 1951 UNITED STATES PATENT OFFICEOOLLAPSIBLE CARTON Lawrence H. Phillips, Chattanooga, Tenn, as-

signor to O. 8. Andrew: Company, Chattanooga Team, a corporation ofTennessee Application October 28, 1949, Serial No. 124,178

3 Claims. (Cl. 229-33) paperboard or similar foldable sheet material,

the cover and the tray being each provided with cooperating lockingmeans for securing them in closed position after the contents have beenloaded in the tray portion.

Among the objects of the invention are to provide compactly collapsibletray and cover sections which can be quickly and conveniently set up bythe simple expedient of raising the front, side and rear walls of thetray to upright position with respect to the bottom of the tray andswinging the side and front walls of the cover portion to a position atright angles to the cover, and to form an extended part or parts on oneof the sections interlocking with apertures or recesses on the othersection whereby to retain the cover and tray interlocked after beingfilled and with the cover brought to closing position.

Another object is to provide means for retaining the side walls inapproximately vertical position after they have been raised from theircollapsed position in which portions of the side walls lie flatagainstthe bottom wall.

Other objects and advantages of the present invention will becomeapparent from the following specification and in the claims appendedthereto.

In the drawings, illustrating a preferred embodiment of the invention-Fig. l is a perspective view, illustrating the carton in an opencondition ready to receive contents;

Fig. 2 is a fragmentary top view of the tray, illustrating the means forretaining the side walls in approximately vertical position;

Fig. 3 is a fragmentary sectional view along line 3-3 of Fig. 2;

Fig. 4 is a fragmentary side view of the carton in partially openedcondition, and with certain portions broken away;

Fig. 5 is a fragmentary side view, illustrating the tray and cover inlocked position;

Fig. 6 is a fragmentary sectional view of the cover portion,illustrating one of the cover locking elements; and

Fig. 7 is a fragmentary plan view illustrating the construction of thefront corner portion of the carton blank.

In general the carton of the present invention in its preferred formcomprises a tray with front, rear and side walls integral with the traybottom and a cover integral with the rear wall of the tray having frontand side walls or flanges. The front and rear walls of the tray are eacharranged to fold inwardly to lie flat on the tray bottom and the twoside walls are diagonally creased so as to be foldable in part upon thetray bottom and at the same time remain se-.

cured at their ends to the front and rear walls by means of suitablecorner flaps connecting the sides to such walls. The side flanges of thecover are also diagonally creased and secured to the front wall of thecover by corner flaps thus enabling the side flanges or walls of thecover to be collapsed in part to lie flat against the under side of thecover. The cover and its flanges, when collapsed, are adapted to liesubstantially flat against portions of the bottom of the tray and itsattached collapsed side walls and front wall. A locking detent ispreferably formed as a rigid extended portion at each lower front cornerof the tray, such detents being adapted to be received in suitableopenings formed at the corners of the cover section along the line ofjuncture of the front and side walls of the tray section.

Referring to the drawings. the carton is preferably in the form of aone-piece blank and comprises a bottom tray portion indicated generallyat I 0 and a cover portion indicated generally at H. The tray portioncomprises a bottom panel l2, front and-rear walls l3 and i4 and sidewalls l5, IS. The cover portion comprises a main panel IT, a front walll8 and side walls l9, l9. Crease lines 20 and 2| are impressed in theblank to separate the front wall i3 and rear wall M, respectively, fromthe bottom panel l2, and crease lines 22 and 23 are impressed in theblank to separate the rear wall and the front wall 18 of the cover fromthe cover panel ll. Crease lines 25, 25 are impressed longitudinally ofthe blank to separate the tray side walls l5, I5 from the bottom panell2, and crease lines 26, 26 are impressed in alignment with the creaselines 25, 25 to separate the cover side walls l9, l9 from the coverpanel H.

The side walls l5, 15 of the tray are secured to the rear wall M bymeans of corner flaps 21, 21 carried on the rear ends of the side wallsand are separated therefrom by crease lines 2la, 2la which areextensions of the crease line 2|. For the purpose of connectingthe sidewalls l5, l5 to the front wall l3 the ends of wall I3 are provided withcorner flaps 28, 28 preferably of rectangular shape. These flaps aredefined from the front wall I3 by means of crease lines 25a, 25a formingextensions of crease lines 25, 25.

In order to make the tray portion collapsible diagonal crease lines 29,29 are impressed in the walls I5 and extend from the intersecting pointof crease lines 2I and at an angle of approximately 45 to the outer edgeof each of the walls I5. There is thus defined between the crease lines2Ia and 29 a rear triangular portion 30 in each side wall. Additionaldiagonal crease lines 3|, 3| are impressed in the side walls I5 whichextend from the intersection of the crease lines 20 and 25 at an angleof approximately 45 to the outer edge of each side wall. There is thusdefined between the crease line 3I and the forward edge of the side wallI5 a forward triangular portion 32 in each side wall.

The corner flaps 21, 21 are preferably secured as by means of anadhesive to the inside surface of the rear wall I4 and the corner flaps28, 28 are preferably secured to the inner side of the side wall I5 onlywithin the area of the forward triangular portions 32, 32. Due to thearrangement just described the central portion of each wall I5, I5 maybe folded down against the bottom panel I2 and, simultaneously with suchmovement, the rear and forward triangular portions of the walls I5, I5will be folded over against the central portion of such Walls and thefront and rear walls will be folded inwardly and downwardly against thetriangular portions in a position overlying the bottom panel I2. In suchcollapsing the corner flaps 28, 28 will be so moved that they will cometo rest flat against the inner surface of the front wall I3.

It is to be understood that the carton, in practice, will be constructedin a series of gluing operations in which the carton will be completelymanufactured in a collapsed condition and that it will not ordinarily benecessary for the carton to be collapsed after it has once been set upfor use.

The side walls I9, I 9 of the cover portion are preferably secured tothe cover front wall IB by means of a corner flap 33 carried by theforward end of each side wall I 9. Each flap 33 is hingedly joined toside wall I9 along the crease line 23a which forms an extension of thecrease line 23 between the top panel I! and the front wall I8. In orderto enable the cover portion of the carton to be formed in collapsedcondition a crease line 34 will be impressed in each cover side wall I9along the diagonal line extending from the intersection of the creaselines 23 and 26 to the outer edge of the cover side wall I9, thusdefining a forward triangular portion 35 in the forwaid edge oi eachside wall I9.

The cover portion of the carton, due to the arrangement just described,may be manufactured in collapsed condition by having the main portionsof the cover side walls I9, I9 folded flat against the panel II with theforward triangular portions 35, 35 folded over against such mainportions of the side walls and with the front wall I8 brought to aposition overlying the triangular portions and the main panel I1.

Cooperating parts are provided on the tray and the cover for locking thecover in place on the tray after it has been filled with contents. Forthis purpose a projecting part is provided at one or both front cornersof the tray and a recess or opening is provided at a corresponding frontcorner or both front corners of the cover for receiving such projectingpart thus to hold the cover in alignment with the crease line 20.

4 locked in closed position upon the tray. 'In the preferred form of theinvention the forward triangular portion 32 of the tray side wall isformed with a projecting tab or detent 31 which is of such size as toextend forwardly slightly beyond .the plane of the front wall I3after-the front wall has been connected to the side walls I5, I5 bysecuring each comer flap 28 to the triangular portion 32, as previouslydescribed. The lower edge 38 of the detent 31 is preferably out along aline which is approximately parallel to the bottom wall I2 to provide alocking edge. The upper edge portion 39 of the detent is preferably outalong an inclined line for a purpose presently to be described.

The edge of the forward triangular portion 32,

lying above the detent 31, as indicated at 40, is

preferably cut back out of alignment with the front edge of thetriangular portion which lies below the detent. The edge portion 40 isalso preferably inclined rearwardly at a slight angle to a line which isnormal to the bottom panel I 2. The cutting of the edge 40 as justdescribed permits of a relationship with the front corner of the traywherein the edge 40 will be spaced rearwardly of such front corner.

The cover portion is provided, as herein illustrated, with a detentreceiving opening 4| preferably formed adjacent the crease line 23awhich constitutes the hinge between the front cover wall I8 and the sidewall I9. While the opening 4| may be formed in different manners it ispreferably formed by making a U-shaped slit with the ends of the slitterminating approximately on the crease line. The crease line 23a ispreferably interrupted between the ends of the U-shaped slit thusproviding a portion 42 which remains in the plane of the triangularportion 35. Thus, when the corner flap 33 is moved at an angle to itsconnected triangular portion 35, the portion 42 will remain in the planeof the triangular portion 35 and the detent receiving opening 4| will bemade effective and ready'to receive the detent 31.

Means are provided for maintaining the tray in set-up condition. Forthis purpose one or more abutment portions in the form of raised orembossed lines or nubs 44 are indented inwardly of the bottom panel I2to form upwardly projecting portions in a position to be engaged by thelower edge of each corner flap 28. As indicated in Fig. 7, the detent 31is cut from stock that would otherwise be a part of the corner flap 28if the lower edge of such flap was extended outwardly Advantage is takenof this feature by continuing the cut of the lower edge of the cornerflap 28 outwardly upon the offset line necessitated by the provision ofthe detent 31. When the corner flap 28 is secured to the forwardtriangular portion 32 of the tray side wall the securing of these partsis preferably done in such manner that the front wall I3 will bedisposed at a slight angle inwardly of a line which is normal to thebottom panel I2. By this arrangement the hinge lines for the cornerflaps 28 are tilted rearwardly of the tray and the lower free comerportions of each of the corner flaps are caused to drag along the innersurface of the bottom panel I2 as soon as such outer free cornerportions approach a position adjacent the crease lines 25 between thebottom panel and its attached side walls. The

embossed lines or nubs 44 are impressed in the bottom panel at suchposition so as to be engaged by the outer free edges of the comer flaps28 as they drag along the surface of the bottom panel when the box isopened and in this way the embossed lines or nubs 44 tend to resistretrogressive movement of the fiaps 28 once the flaps have been moved toa position approximately flat against the walls l5.

In the use of the carton of the present invention it will be completelyformed by suitable gluing mechanism in collapsed form in a manner whichis well known, and in such condition will be delivered to the packer.When the carton is ready to be filled it is usually opened by automatichigh speed machinery which delivers the carton to filling mechanismimmediately after it has been opened. The presence of the embossed linesor nubs 44 tends to assure that the tray, after being opened, willremain in opened condition until the carton reaches the fillingmechanism. After the tray part has been filled with the desiredcontents, usually food products which are later to be quick frozen, thepresence of such contents in the tray will serve to square up the trayand maintain the side walls I5, in straight condition.

After filling the tray the cover portion is expanded and will be swungdown over the filled tray. As the cover portion approaches its finalposition the edge of the front wall will slide over the inclined edge 39of the detents and thereafter the detents 37 will be received into thedetent-receiving openings 4i, 4! and the parts will come to rest withthe straight portion 38 of each detent in engagement with the lower edgeof each opening 4 l. The detent 31 is made sumciently short so that itwill not extend appreciably beyond the plane of the outer surface of 1the cover front wall 18. Likewise the U-shaped slit which releases theportion 42 will be made sufficiently small so that the part 42 also willnot extend appreciably beyond the plane of the outer surface of thefront wall l8. By this construction the locking parts will not be in anyway unsightly and will not interfere with mechanical wrapping mechanismif the filled and closed cartons are to be enclosed within a wrapper.

While the present description sets forth a preferred embodiment of theinvention, certain changes may be made in the construction withoutdeparting from the spirit of the invention, and it is therefore desiredthat the present embodiment be considered in all respects asillustrative and not restrictive, reference being had to the appendedclaims rather than to the foregoing description to indicate .the scopeof the invention.

I claim:

1. A paperboard carton including a tray and a cover of substantially thesame depth hinged along the rear edges thereof, the tray comprising abottom panel with a front wall, rear wall and end walls substantiallyperpendicular thereto extending from the edges thereof, the front endedge of each of the end walls adjacent the front wall being offsetinwardly of the plane of said front wall a substantial distance andhaving a projection extending outwardly of the plane of the front wall,the cover comprising a top panel with front and end walls correspondingto said tray walls adapted to extend about the tray walls when the coveris disposed over the tray, the cover wall corresponding to said frontwall of the tray having an opening therein at each end thereof adaptedto receive said projection upon disposition of the cover over the trayto prevent separation thereof, the offset relation of said end edgeaffording positive clearance between the outer corner formed by saidtray walls and the inner corner defined by said cover walls, wherebyjamming of the cover in closing movement over the tray is prevented andpositive locking engagement of the projection in the opening isfacilitated.

2. A paperboard carton as set forth in claim 1 wherein the front traywall is inclined inwardly at slightly less than a right angle to thehollow panel to facilitate disposition of the cover over the tray.

3. A paperboard carton including a tray and a cover of substantially thesame depth, hinged along the rear edges thereof, the tray comprising abottom panel with a front wall, a rear wall, and side wallssubstantially perpendicular thereto extending from the edges thereof,the front end edge of each of the side walls adjacent the front wallbeing offset inwardly of the plane of the said front wall a substantialdistance, projections extending outwardly of the planes of the walls atthe front corners, the cover comprising a top panel with front and sidewalls corresponding to said tray walls adapted to extend about the traywalls when the cover is disposed over the tray, the cover walls havingopenings therein at the front corners adapted to receive saidprojections upon disposition of the cover over the tray to preventseparation thereof, the offsetrelation of said end edges affordingpositive clearance between the outer corners formed by said tray wallsand the inner corners defined by said cover walls, whereby jamming ofthe cover in closing movement over the tray is prevented and positivelocking engagement of the projections in the openings is facilitated.

LAWRENCE H. PHILLIPS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

